Insulation product with inward curling closure flap

ABSTRACT

A pipe insulation product including a core of insulating material and a laminate surrounding the core and bonded to the core. The core may include an outer surface; an inner surface; and a wall extending between the outer and inner surfaces. The laminate may include a foil or metallized polymeric film sheet, a scrim, a porous media sheet, and a polymeric film sheet bonded together via an adhesive. The laminate may include a closure flap that is configured to adhesively seal opposite ends of the laminate together to form a cylindrical tube with the core enclosed therein. The closure flap may be configured to include a curl that provides a greater closure flap adhesive seal.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a divisional of pending Non-Provisional U.S. patentapplication Ser. No. 15/436,490 filed Feb. 17, 2017, which is acontinuation of Non-Provisional U.S. patent application Ser. No.12/855,833 filed Aug. 13, 2010, now abandoned. This application isrelated to Applicant's U.S. Pat. No. 9,376,814 issued Jun. 28, 2016entitled “Systems and Methods for Insulating a Pipe”; Applicant's U.S.Pat. No. 8,104,519 issued Jan. 31, 2012 entitled “Pipe InsulationProduct with Charge Dissipater”; and, Applicant's U.S. Pat. No.8,141,594 issued Mar. 27, 2012 entitled “Pipe Insulation Products andMethods”.

The entire disclosures of the aforementioned Non-Provisional U.S. patentapplications and U.S. patents are hereby incorporated by reference, forall purposes, as if fully set forth herein.

BACKGROUND OF THE INVENTION

The subject invention relates generally to pipe insulation products andmore specifically to pipe insulation products comprising an insulatingmaterial core enclosed within a laminate jacket.

Piping is often used to transport one or more fluids betweendestinations. For example, piping may be used to transport water,petroleum, oxygen, etc. The piping is often made from a metal material,such as copper, stainless steel, galvanized steel, aluminum, brass,titanium, etc., or from a plastic material, such as polyvinyl chloride(PVC), chlorinated polyvinyl chloride (CPVC), fiber reinforced plastic(FRP), polypropylene (PP), polyethylene (PE), etc. Piping may also bemade from a ceramic, fiberglass, or concrete material, although thesepipes are less common.

During fluid transportation, the fluid may be subjected to heatingand/or cooling from the surrounding environment. For example, the fluidmay be transported in either a hot or cold state relative to thesurrounding environment, which induces heat transfer to or from thefluid and pipes. HVAC systems are a common example of systems thatroutinely utilize various pipe configurations to transport hot or coldfluids. Due to the conductive nature of the pipes (especially metalpipes), heat may be conducted to or from the fluid duringtransportation. The addition or removal of heat may result in thedecreased efficiency of a system and/or increased time and/or expense inoperating the system. For example, in HVAC systems, the addition of heatto cooled fluids may result in loss of efficiency for a cooling unit andmay also result in increased expense because of increased operating timeand energy needed to achieve a desired cooling level.

To reduce heat transfer during fluid transportation, pipe insulationproducts are commonly installed on one or more sections of pipes toretard the flow of heat to or from the pipes. Commonly, one or moresections of pipe are fitted with a pipe insulation product where thesections of pipe are generally fully encased within the pipe insulationproduct. Separate sections of the pipe insulation product are oftencoupled together via adhesive tapes. The outer surface of the pipeinsulation product is often designed to enhance the visual appeal of thepiping system and serve as a means for sealing the pipe insulationproduct about the pipes of the piping system. In addition, the variouslayers of the pipe insulation product often serve one or more importantfunctions (e.g., restricting water vapor transmission; resisting mold,mild, and/or fungal growth; providing puncture resistance, tensilestrength, and/or durability; resisting UV, handling, environmental,and/or shipping damage, etc.).

To perform some of these functions, it is critical that the outer layerof the pipe insulation product be sealed and remain sealed over the lifeof the pipe insulation product. For example, the pipe insulation productmay include one or more layers that restrict the transmission of watervapor or other environmental contaminants through the laminate.Generally, a pipe insulation product is required to have a water vaportransmission rate of no greater than 0.02 perms. If the pipe insulationproduct is not able to seal and/or remain sealed over the life of theproduct, the layer that functions as a water vapor barrier or retardermay be compromised or circumvented because water vapor and/or othercontaminants may freely flow through the unsealed portion of the pipeinsulation product.

Leakage of water vapor and/or other contaminants into the pipeinsulation product's interior may cause a variety of problems for theinsulated pipe and/or surrounding objects including: condensation ofwater on the pipes; mold, mildew, or fungal growth; pipe corrosion ordegradation; staining of the pipe insulation product and/or surroundingobjects; water drip damage; loss of the pipe insulation product'sinsulating value, etc. Hence, the integrity of the pipe insulationproduct's seal is critically important to the functionality of the pipeinsulation product.

BRIEF SUMMARY OF THE INVENTION

One embodiment of the present invention may include a pipe insulationproduct for insulating a pipe. The pipe insulation product may include atubular core of insulating material and a laminate that is roughlyrectangular in shape, that is and bonded to the tubular core, and thatis flexible so that the tubular core and laminate can be opened, placedabout a pipe, and closed without degrading the laminate.

The tubular core may include a length and a longitudinal axis; asubstantially cylindrical outer surface; a substantially cylindricalinner surface; and a wall extending between the cylindrical outersurface and the cylindrical inner surface. The wall may include aradially extending thickness and a slit that extends completely throughthe wall from the outer surface to the inner surface and that extendsparallel to the longitudinal axis of the tubular core for the length ofthe tubular core.

The laminate may include a polymeric film sheet that forms an outerexposed layer of the laminate; a foil or metallized polymeric sheetmaterial that provides a fluid vapor barrier to minimize fluid vaportransmission through the laminate; a scrim comprising a mesh of aplurality of fibers; a porous media sheet; and an adhesive that bondsthe foil or metallized polymeric sheet material, the scrim, the porousmedia sheet, and the polymeric film sheet together to form the roughlyrectangular laminate.

The laminate may also include a closure flap that is configured toadhesively seal opposite sides of the laminate in a closed position sothat the laminate forms a substantially cylindrical tube with at least aportion of the tubular core enclosed therein. The closure flap may beconfigured to include a curl that provides a greater closure flapadhesive seal bond. The porous media sheet may include a kraft paperbetween the range of 25 and 35 pounds per 3000 square feet to provide agreater closure flap adhesive seal bond by increasing the flexibility ofthe laminate.

Configuring the closure flap to include a curl may comprise eitherreducing an amount of curl already present in the closure flap, wherethe present curl is a curling of the closure flap away from the closedposition (i.e., reverse curl); or may include configuring the closureflap to curl toward the closed position. Configuring the closure flap toinclude a curl may also comprise controlling an amount of tension in thepolymeric sheet material and an amount of tension in one or more of theother layers during lamination of the layers so that, after lamination,the tension in the polymeric sheet material is less than the tension inthe one or more of the other layers. Configuring the closure flap toinclude a curl may further comprise securing the closure flap in theclosed position, heat treating the laminate to soften the polymericsheet material, and cooling the polymeric sheet material so that thepolymeric sheet material hardens with the closure flap curled toward theclosed position.

Configuring the closure flap to include a curl may additionally comprisearranging at least one laminate so that the closure flap is positionedin the closed position and maintaining or holding the laminate with theclosure flap in the closed position for a period of time so that, afterthe period of time, shape memory is induced in the closure flap.Configuring the closure flap to include a curl may additionally comprisepositioning the scrim between the porous media material and thepolymeric sheet material to either provide improved control over thetensioning of one or more of the polymeric sheet material, the porousmedial material, and the foil or metallized polymeric sheet material; orto provide increased stability to the polymeric sheet material.

Configuring the closure flap to include a curl may additionally compriseeither controlling the temperature of an adhesive used to bond thelaminate and tubular core to minimize heat dissipation from the adhesiveto the polymeric sheet material; or cooling the tubular core ofinsulating material to roughly ambient temperature prior to bonding thetubular core and the laminate to minimize heat dissipation from theinsulating material to the polymeric sheet material. Configuring theclosure flap to include a curl may additionally comprise eithercontrolling the size and configuration of the fibers of the scrim fibermesh to reduce a curl of the closure flap away from the closed position;or configuring the scrim fiber mesh to include one or more fibersconfigured to provide the closure flap with a positive curling forcetoward the closed position.

Another embodiment of the present invention may include a method forproducing a roughly rectangular laminate that provides a greaterlaminate seal. The method may include providing a foil or metallizedpolymeric sheet material that forms an inner layer of the laminate andthat provides a fluid vapor barrier to minimize fluid vapor transmissionthrough the laminate. The method may also include providing a polymericsheet material that is coextensive with the foil or metallized polymericsheet material and that forms an outer exposed layer of the laminate.The method may further include providing a scrim comprising a mesh of aplurality of fibers where the scrim is coextensive with the foil ormetallized polymeric sheet material. The method may additionally includeproviding a porous media sheet material.

The porous media sheet material may be coextensive with the foil ormetallized polymeric film sheet. The scrim and porous media sheetmaterial may be positioned between the foil or metallized polymeric filmsheet and the polymeric film sheet. The method may additionally includebonding the foil or metallized polymeric sheet material, the scrim, theporous media sheet material, and the polymeric sheet material togetherwith an adhesive to form the laminate jacket. The laminate jacket mayinclude a closure flap that is configured to adhesively seal oppositesides of the laminate jacket in a closed position so that the laminatejacket forms a hollow cylindrical tube. The method may additionallyinclude configuring the closure flap to include a curl that provides agreater closure flap adhesive seal bond.

The method for producing a laminate jacket may additionally includebonding a tubular core of insulating material with the laminate jacket.The method for bonding the tubular core and laminate jacket may includepositioning a tubular core of insulating material directly adjacent tothe foil or metallized polymeric sheet material. The method may alsoinclude bonding the tubular core of insulating material with the foil ormetallized polymeric sheet material with an adhesive material. Thelaminate and tubular core may be flexible so that the tubular core andlaminate jacket can be opened, placed about a pipe, and closed withoutdegrading the laminate jacket. The method may further include flexingthe tubular core and laminate jacket to open the laminate jacket andtubular core; placing the laminate jacket and tubular core about thepipe; and closing the laminate jacket and tubular core about the pipe byapplying pressure to the closure flap to adhesively seal the oppositesides of the laminate jacket.

Another embodiment of the present invention may include a roughlyrectangular laminate. The laminate may include a polymeric film sheetforming an outer exposed layer of the laminate; a foil or metallizedpolymeric sheet material the provides a fluid vapor barrier to minimizefluid vapor transmission through the laminate; a scrim comprising a meshof a plurality of fibers; a porous media sheet; and an adhesive thatbonds the foil or metallized polymeric sheet material, the scrim, theporous media sheet, and the polymeric film sheet together to form theroughly rectangular laminate. The laminate may include a closure flapthat is configured to adhesively seal opposite sides of the laminate ina closed position so that the laminate forms a substantially cylindricaltube. The closure flap may be configured to curl toward the closedposition to provide a greater closure flap adhesive seal bond.

The foil or metallized polymeric film sheet may form an inner layer ofthe laminate and the porous media sheet may be positioned immediatelyadjacent to the foil or metallized polymeric film sheet so that the foilor metallized polymeric film sheet lies substantially flat against theporous media sheet. The configuration of the substantially flat foil ormetallized polymeric film sheet may provide an improved perm rating forthe laminate.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic perspective view of a pipe insulation product thatincludes a core of insulating material encased within a laminate jacket.

FIG. 2 is a schematic perspective view of a laminate jacket according toone embodiment of the present invention with portions of the laminatebroken away to show the various layers of the laminate.

FIG. 3 is a schematic perspective view of a process for manufacturing alaminate.

FIG. 4 is a schematic perspective view illustrating a process forinducing an inward curling closure flap.

FIG. 5 is a schematic perspective view illustrating another process forinducing an inward curling closure flap.

FIG. 6 is a schematic perspective view illustrating laminates of thepresent invention having different layer configurations.

FIG. 7 is a schematic perspective view of various scrim fibers that maybe used to induce an inward curling closure flap.

FIG. 8 is a flow diagram illustrating a method for manufacturing a pipeinsulation product.

DETAILED DESCRIPTION OF THE INVENTION

The present invention includes a pipe insulation product that may beused to insulate a pipe and to provide one or more other beneficialproperties. For example, the pipe insulation product may serve anaesthetic purpose when fitted about pipe sections. Pipe insulationproducts are often designed to provide a smooth, finished, and visuallyappealing outer surface to enhance the visual appeal of the pipingsystems. In addition, the pipe insulation product may also shield orprotect the pipe from one or more environmental elements (e.g., watervapor). The protection/shielding function minimizes potential risks forthe pipe and/or for surrounding objects (e.g., minimizes condensation ofwater on the pipes; mold, mildew, and/or fungal growth; water dripdamage; loss of the pipe insulation product's insulating value; etc.).To minimize these risks, it is critical that the outer layer of the pipeinsulation product be sealed and remain sealed over the life of the pipeinsulation product. Further, the pipe insulation product must readilyadapt to a wide variety of different climates and conditions in whichthe products are often used and/or installed (e.g., hot, cold, humid,dry, etc.).

Pipe insulation products typically include a tubular core of insulatingmaterial surrounded by and encased within a laminate jacket or laminate.Individual segments of the pipe insulation product typically range inlength from about 36 inches to about 48 inches; have a wall thicknessranging from about 0.5 inches to about 3 inches; and a range in outsidediameter from about 2 inches to about 32 inches.

In addition, the laminate may include one or more layers that providevarious beneficial properties that enhance the performance of the pipeinsulation product. For example, one of the most important functionsthat the laminate serves is to act as a water vapor barrier to protectthe pipe and/or insulating material from water vapor in the surroundingenvironment. Water vapor that is able to pass into the laminate'sinterior may condensate on the pipes and/or absorb into the insulatingmaterial, which may cause pipe corrosion or degradation; mold, mildew,and/or fungal growth; water drip damage; staining of the laminate and/orsurrounding objects; loss of the pipe insulation product's insulatingvalue; etc.

To provide the water vapor barrier function, laminates typically includean aluminum foil layer that reduces the transmission of water vaporand/or other contaminants through the laminate. In addition, laminatestypically include a closure flap and adhesive material that allows theends or edges of the laminate to be sealed in a closed position so thatthe laminate forms a sealed hollow tube fully encasing the pipe andinsulating material (the unsealed laminate allows the laminate andtubular core to be opened and placed about a pipe). The failure of theclosure flap to seal and/or remain sealed may compromise or circumventthe laminate's water/contaminant barrier function because water vaporand/or other contaminants may freely flow through the unsealed portionof the laminate into the interior.

In some instance, the configuration of the pipe insulation product maycontribute to the inability of the closure flap to seal and/or remainsealed. For example, some laminate jackets include a polymeric filmmaterial outer layer. The polymeric film material may be selected as theouter layer to provide one or more advantages including: durability,wrinkle resistance, stain resistance, mold resistance, aesthetic appeal,etc. However, the closure flap of laminates that include a polymericfilm outer layer may have a tendency to curl away from the sealingposition, or in other words “reverse curl” (i.e., the closure flap maycurl away from the position it occupies when the laminate is closed orsealed). The reverse curl of the closure flap may impart a lifting forceon the adhesive material that seals the laminate, which may facilitatein failure of the seal. In addition, the inclusion of the polymeric filmmaterial outer layer may increase the stiffness and rigidity of thelaminate, which may impede the ability of the closure flap to be curledtoward the sealing position and remain in the sealing position. Further,the various different climates and conditions that the pipe insulationproduct may be subjected to, and therefore must adapt to, may increasethe likelihood that the closure flap's seal will fail.

The present invention provides a laminate with closure flap having areduced “reverse curl,” or in some embodiments provides a laminate witha closure flap having a “positive curl” where the closure flap curlstoward the sealing position (i.e., the closure flap may curl toward theposition it occupies when the laminate is closed or sealed). A laminatewith a reduced reverse curl or a positive curl may increase theintegrity of the closure flap seal (i.e., may provide for a greaterclosure flap adhesive seal bond) by reducing a lifting force and/orimparting a closure force (i.e., a force biasing the closure flap towardthe closed position). Additionally, the reduced reverse curl and/orpositive curl may increase the integrity of the seal, and hence reducethe seal's failure rate, over a wide variety of different climates andconditions to which the pipe insulation product may be exposed. In otherwords, the present invention may allow a single pipe insulation productto be used in a variety of conditions because of the product's increasedability to maintain a closed sealed position in all conditions. Theseand other advantages of the present invention will become more evidentwith reference to the figures.

As shown in FIG. 1, a pipe insulation product 100 may include a tubularcore of insulating material 104 that may include a substantiallycylindrical outer surface (i.e., the outside of the tubular core thatdirectly contacts the laminate) and a substantially cylindrical innersurface 114. Extending between the cylindrical outer surface and thecylindrical inner surface 114 may be a wall of insulating material. Theinsulating material provides the insulating properties of the pipeinsulation product 100. In one embodiment, the insulating material maybe a fibrous material (e.g., fiberglass, mineral wool, refractoryceramic fiber, chopped strand fiber glass, etc.). In other embodimentsthe insulating material may be a foam (e.g., phenolic foam,polyisocyanurate, polyolefin, polystyrene, polyurethane), a polymer,foam glass, microporous insulation (e.g., Microtherm®), or any othermaterial that provides insulation.

The cylindrical inner surface 114 may be configured to correspond with aspecific pipe outer diameter (e.g., ½ inch, 1 inch, etc.). The tubularcore 104 may also include a longitudinally extending slit 112 thatpasses completely through the wall of insulating material on one sideand into the interior of the substantially cylindrical inner surface 114so that the tubular core 104, and thus, the pipe insulation product 100,can be opened, passed over, and closed about a pipe.

Circumferentially surrounding and encasing the tubular core 104 is alaminate jacket or simply a laminate 102. The laminate 102 has athickness 106 that includes one or more layers of various materials asdescribed below. The laminate 102 is roughly co-extensive with thetubular core 104 and bonded to the cylindrical outer surface. Thelaminate 102 may be positioned so that a longitudinal edge portion 116extends parallel and adjacent to the slit 112, but does not overlap theslit 112. The laminate 102 includes a closure flap 108 that may have apressure sensitive adhesive layer 110 so that the laminate 102 may beadhesively sealed in a closed position fully encasing the tubular core104 within the laminate 102. The laminate may be sealed by folding oroverlapping the closure flap 108 over the longitudinal edge portion 116of the laminate 102 and by applying pressure to the pressure sensitiveadhesive layer 110 so that the closure flap 108 adhesively seals to theouter surface of the overlapped portion of the laminate 102.

In some embodiments, the closure flap 108 may curl outward, meaning thatthe closure flap 108 curls away from the closed position (FIG. 1 showsthe outward or “reverse” curl of the closure flap 108). In suchembodiments, the outward or reverse curl must be overcome in order toadhesively seal the closure flap 108 to the laminate's outer surface.The reverse curl of the closure flap 108 may impart a lifting force onthe adhesive material after the closure flap 108 is sealed, which maycause the closure flap 108 to become unsealed at some time during thelaminate's 102 lifetime (i.e., the reverse curl may cause the closureflap 108 to peel back away from the sealed position). The closure flap'stendency to unseal or peel back may be enhanced under some environmentalconditions and/or may be enhanced as those conditions change (i.e.,unsealing or peeling back may be accelerated due to high heat andhumidity, due to repeated change from high to low temperatures, etc.).The reverse curl may be due to the stiffness of the porous media layer;stiffness, shrinkage, and/or internal stress within the polymeric filmsheet layer; etc.

In other embodiments, the closure flap 108 may not have a reverse curl,but may be biased toward a straight or flat position due to thestiffness of the laminate and/or one or more layers of the laminate(i.e., the porous media layer, the polymeric film material, etc.). Asadditional layers are added to the laminate, the stiffness may increase,which may cause and/or enhance the closure flap 108 sealing problemsdiscussed herein.

The closure flap 108 may include a removable silicone treated releasestrip (not shown) removably adhered to the pressure sensitive adhesivelayer 110 to protect the adhesive material from degradation prior toinstallation. Maintaining a sealed closed position is a criticalfunction of the closure flap 108 and adhesive layer 110 so that theinsulated pipe and/or insulating material are not subjected to one ormore environmental elements, such as water vapor. If the closure flap108 is not able to seal or remain sealed (e.g., the closure flap 108curls backward after being adhered to the laminate's outer surface),then water vapor and/or other contaminants may flow between the closureflap 108 and longitudinal edge portion 116 and thereby leak or pass intothe interior of the pipe insulation product (i.e., pass to the encasedpipe and insulating material). Water vapor and/or other contaminantsthat pass into the laminate's interior may cause condensation of wateron the pipes; pipe corrosion or degradation; mold, mildew, and/or fungalgrowth; water drip damage; staining of the laminate and/or surroundingobjects; loss of the pipe insulation product's insulating value; etc.

The laminate 102 may include one or more flame retardants, fungi growthinhibiting agents, charge dissipators, and/or other additives to enhancethe performance of the laminate. Additionally, butt strips (not shown)may be used to connect individual segments of the pipe insulationproduct end to end. The butt strips may be strips of adhesive material(i.e., tape) that are substantially impermeable to fluid vapors togreatly restrict or eliminate the transmission of water vapor throughthe butt strips (i.e., the butt strips seal end segments of the pipeinsulation product 100 together). The butt strip's ability to seal theend segments may also be compromised due to the closure flap's tendencyto peel back or unseal.

FIG. 2 depicts a laminate jacket 200 according to one embodiment of thepresent invention. FIG. 2 shows portions of the laminate 200 broken awayto reveal the various layers of the laminate. The laminate 200 mayinclude an inner layer composed of a foil or metallized polymeric filmsheet 208. Preferably, the laminate 200 includes an inner layer that ismade of aluminum foil or metallized polyethylene terphthalate (MPET)between about 0.48 mils and about 100 mils in thickness (between about48 and 100 gauge in thickness). The inner layer aluminum foil or MPETprovides a nearly impermeable fluid vapor barrier to fluids that areexternal to and surrounding the pipe insulation product. For example,the foil or metallized polymeric film sheet 208 is nearly impermeable towater vapor, which protects the insulated pipe from water condensation,corrosion, loss of insulating value, mold growth, etc. The foil ormetallized polymeric film sheet 208 enables the laminate 200 to providea water vapor transmission rate of less than 0.02 perms.

By using the foil or metallized polymeric film sheet 208, fluid may bepassed through the insulated pipe and one or more environmental elements(e.g., water vapor) in the surrounding environment may be restricted (orkept) from penetrating through laminate to the pipe. When cold fluid ispassed through the pipe, the foil or metallized polymeric film sheet 208prevents water vapor from condensing on the pipes and causing theassociated problems described herein. If the closure flap 108 becomesunsealed, however, the water vapor barrier is circumvented as watervapor may freely flow between the unsealed portion of the laminate.Although the foil or metallized polymeric sheet 208 is described as theinner layer of the laminate 200, the foil or metallized polymeric sheet208 may be positioned anywhere within the laminate (e.g., immediatelyadjacent the polymeric sheet outer layer).

The laminate 200 may also include a scrim 206 the includes a mesh of aplurality of fibers. The scrim 206 may function to reinforce andstrengthen the laminate 200 and thereby provide increased tensilestrength, puncture resistance, etc. The scrim 206 may be made offiberglass reinforcing yarn, such as but not limited to a G75 or H110yarn. In addition, the yarn may be configured to be from 2 to 6 strandsper inch in both the machine and cross machine directions, with atypical scrim being about 5 strands per inch in both directions. In someembodiments the scrim 206 may be made of polyester strings or any othersynthetic string. The scrim 206 may be positioned immediately adjacentto the foil or metallized polymeric sheet 208 or may positioned anywhereelse within the laminate (i.e., may be positioned immediately adjacentthe polymeric sheet outer layer 202).

The laminate 200 may also include a porous media sheet 204. The porousmedia sheet 204 may be positioned immediately adjacent to the scrim 204or may be positioned anywhere else within the laminate 200. The porousmedia sheet 204 may be a kraft paper that is between about 25 and 45pounds/3000 square feet and may include one or more additives to enhancethe performance of the laminate 200 (e.g., fire retardant additivesand/or anti-microbial agents to prevent mold or fungal growth andprevent propagation of smoke and/or fire). In one embodiment, the porousmedia sheet 204 may be a kraft paper between 25 and 35 pounds/3000square feet to provide increased seal integrity and/or closure of theclosure flap 108 without significantly degrading beneficial propertiesof the laminate (e.g., tensile strength, puncture resistance, handlingdamage resistance, etc.). In one specific embodiment, the kraft papermay be roughly 30 pounds/3000 square feet to provide optimal levels ofclosure flap seal integrity and laminate properties.

Alternatively, the porous media sheet 204 may be other materials such asa fiberglass mat, synthetic mat, paper, etc. Likewise, in someembodiments the scrim 206 and porous media sheet 204 may be replaced bya single, preferably porous, material. The porous nature of the porousmedia sheet 204 may allow absorption and retention of one or moreadditives within the porous media sheet layer, which may provide one ormore enhancements to the laminate 200 (e.g., flame and smoke propagationresistance; mold, mildew, and/or fungal growth resistance; etc.).

In laminates that employ a kraft paper, the use of a heavy weight kraftpaper (e.g., 40-45 pounds/3000 square feet) may be preferred becausesuch papers provide several advantages over lighter weight papers (e.g.,25-35 pounds/3000 square feet). For example, heavier weight kraft papersmay provide structural advantages including increased durability,support, tensile strength, puncture resistance, handling damageresistance, environmental damage resistance, shipping damage resistance,etc. and/or may provide aesthetic advantages including a smoother,visually appealing, and more abuse resistant the outer surface. Heavyweight kraft papers, however, may increase that stiffness and rigidityof the laminate, which may increase a laminate's closure flap sealfailure due to the laminate's resistance to bending or curling towardsthe closed position and remaining in the closed position (i.e., stiffand rigid laminates may be biased toward a flat or unsealed position).

The use of a lighter weight kraft paper (e.g., 25-35 pounds/3000 squarefeet) may increase a laminate's closure flap seal integrity bydecreasing the laminate's resistance to bending or curling toward theclosed position. In addition, the lighter weight kraft paper may notsignificantly degrade the beneficial properties of the laminate so thatthe laminate's functionality is not comprised. A paper weight that isroughly 30 pounds/3000 square feet may provide an optimal level of sealintegrity vs. laminate properties. A further description of theadvantages of using a kraft paper between the range of 25 and 35pounds/3000 square feet is provided in U.S. Pat. No. 8,141,594 byShumate et al., entitled “Pipe Insulation Products and Methods,” theentire disclosure of which is incorporated herein.

The present invention, however, is not limited to the use of a lighterweight kraft paper (or to the use of a kraft paper in general). Thepresent invention provides increased closure flap seal integrityregardless of if a heavy weight kraft paper, a light weight kraft paper,or some other porous media layer is used.

The laminate 200 additionally includes a polymeric film sheet outerlayer 202. The polymeric film sheet 202 may be made of polypropylene,polyethylene, polyvinyl chloride, vinyl, saran, polyethyleneterephthalate, thermoplastic polyolefin, etc. The polymeric filmmaterial may be selected as the laminate's outer layer 200 to provideone or more of the following advantages: shielding the porous mediasheet 204 and/or insulating material from water vapor absorption;protecting against UV damage; protecting against mold, mildew, or fungalgrowth; providing a smooth, unwrinkled, visually appealing outersurface; etc. Polymeric film materials generally provide a smoother,more visually appealing outer surface when compared with traditionallaminates.

However, the use of a polymeric film sheet outer layer 202 may result inan increased tendency of the closure flap to curl away from the closedsealed position, or in other words to reverse curl as describedpreviously. The reverse curl may cause and/or enhance closure flap sealfailure due to providing a lifting force against the adhesive material.Seal failure may be further enhanced depending on the climate andconditions the laminate 200 is subject to and/or may be enhanced becausethe polymeric film sheet provides a smoother lower energy surface forthe adhesive material to bond with.

The reverse curl of the closure flap may be caused and/or enhanced bythe inclusion of the polymeric film sheet 202. For example, in someembodiments the tension in the polymeric film sheet 202 (i.e., internalstress) may be greater than the tension in one or more layers within thelaminate 200 (e.g., the porous media layer 204, the scrim 206, and/orthe foil or metallized polymeric film sheet 208). The greater tension orinternal stress in the polymeric film sheet 202 may cause the laminateto curl so that the edges of the laminate bend toward the polymeric filmsheet 202. The increased tension in the polymeric film sheet 202 may bedue to the process of manufacturing the laminate (e.g., the polymericsheet may be tensioned more than the other layers during manufacturing),to shrinkage of the polymeric film sheet 202 after manufacturing (e.g.,heat shrinkage), to cold working the polymeric film sheet 202 and/orlaminate 200, to shape memory within the laminate, or may be due to someother process. In some embodiments, the tension may not be greater inthe polymeric film sheet 202 and the reverse curl may be due to otherfactors (e.g., creasing of the laminate, the shipping configuration ofthe laminate and cold working or shape memory (see description of FIG.5), etc.).

The foil or metallized polymeric film sheet 208, the scrim 206, theporous media sheet 204, and the polymeric film sheet 202 may be bondedor adhered together using one or more adhesives (not shown). Theadhesive or adhesives used may be contact type, pressure sensitive, heatseal, etc. and may include one or more additives to enhance theperformance, dimensional stability, moisture resistance, handleability,fire and smoke propagation resistance, and/or durability of the laminate200. Examples of adhesives that can be used include, but are not limitedto, melamine, urea formaldehyde, phenolic, polyurethane, acrylic, latex,and acrylo-nitrile. Additional adhesives that can be used includeadhesives that can migrate into the porous media sheet 204 to improvethe physical characteristics of the laminate 200 (e.g., improve UVstability, flame spread resistance, mold growth resistance, etc.).Examples of such migrating adhesives are colloidal silica or alumina,sodium or potassium silicate, ammonium phosphate stabilized with zincoxide, magnesia or alumina; borax, and oxi-chloride stabilized with zincoxide or magnesia.

FIG. 3 depicts a process 300 of manufacturing a laminate according toone embodiment of the present invention. The process 300 may be used toinduce an inward curling closure flap (i.e., produce a positive curl)or, alternatively, reduce the amount of reverse curl that a closure flapexperiences due to manufacturing. The process 300 may include aplurality of rollers 306 that may compress a plurality of layers 302 and304 (e.g., the foil or metallized polymeric sheet, scrim, porous mediasheet, and polymeric film sheet) to form a single multilayered laminate.The figures illustrate two layers being compressed together, but thesystem could include other layers. In some embodiments, layer 302includes the polymeric film sheet outer layer and layer 304 includes thefoil or metallized polymeric sheet, the scrim, and the porous mediasheet.

During lamination, tension may be applied to each of the layers 302 and304 (shown by element 312 (tension A) and 310 (tension B),respectively). The layers may be kept in tension during lamination toprevent wrinkles and/or to facilitate winding of the finished laminate.The tension applied to each of the laminates, however, may not beuniform. For example, in some embodiments, tension A, 310, that isapplied to the polymeric film sheet layer 304 may be greater thantension B, 312, that is applied to the other layers 302 of the laminate.The increased tension applied the polymeric film sheet layer 304 mayresult in greater internal stress within the polymeric film sheet outerlayer 304 of the laminate, which may cause the laminate to curl towardthe polymeric film sheet and thereby cause the reverse curl of theclosure flap. In other embodiments, tension A, 310, may be roughlyequivalent to tension B, 312, but shrinkage (e.g., heat shrinkage) afterlamination may cause the internal stress within the polymeric film sheetouter layer 304 to be greater than one or more of the other layers 302.The greater internal stress may result in the reverse curl of theclosure flap.

According to one embodiment of the invention, the tensions, 310 and 312,applied to the layers, 304 and 302, may be controlled to increase thepost lamination tension or internal stress in the other layers 302 ofthe laminate and/or to account for any post lamination shrinkage thatmay occur in the polymeric film sheet layer 304 (i.e., tension A, 310,may be decreased, tension B, 312, may be increased, etc.). As thetension or internal stress in the other layers 302 of the laminate areincreased relative to the polymeric film sheet layer 304, the reversecurl may be reduced and/or a positive curl may be induced so that theclosure flap curls toward the closed sealed position (i.e., the tensionor internal stress within the other layers 302 will cause the laminateto curl toward the inner layer of the laminate).

FIG. 4 depicts another process 400 for reducing a closure flap's reversecurl and/or inducing a positive inward curl. The process 400 may includea laminate 402 surrounding and bonded to a tubular core of insulatingmaterial 404 as previously described. The laminate 402 may include apolymeric film material outer layer having a closure flap 408 with areverse curl. The reverse curl may be reduced and/or a positive curlinduced by positioning the closure flap 408 in the closed position,securing the closure flap 408 in the closed position, heat treating thelaminate to soften the polymeric sheet material (i.e., relaxing thepolymers to reduce or eliminate the internal stress or tension), andcooling the polymeric film sheet so that the polymeric sheet materialhardens or sets and recrystallizes or reforms with a reduced reversecurl or with a positive curl (i.e., the polymeric sheet material hardenswith the closure flap curling toward the closed position).

FIG. 4 illustrates the closure flap 408 being secured in the closedposition through the use of a plurality of straps 422, but any securingdevice, mechanism, or method may be used to secure the closure flap 408in the closed position. For example, the securing device may include oneor more adhesives, weights, clamps, molds, clips, bands, jackets, etc.Further, the laminate may be heated and/or cooled using a variety ofprocess such as ovens (radiation, microwave, etc.), blowers, heatingelements, fans, etc. The laminate 402 may be kept in the securedposition until prior to installation to further configure the closureflap with the positive curl (i.e., induce shape memory).

FIG. 5 depicts another process 500 for reducing a closure flap's reversecurl and/or inducing a positive inward curl. The figure illustrates aplurality of laminates 502 stacked atop one another. Each laminate 502of the plurality of laminates may include a securing device ormechanism, such as a strap 522, to secure the laminate's closure flap508 in a closed position. In some embodiments, the laminates 502 do notinclude a securing device, but are arranged so that the closure flap ispositioned in the closed position as the laminates are stacked atop oneanother. The arrangement of the laminates may secure the closure flap inthe closed position (i.e., the adjacent laminates may secure the closureflap). The plurality of laminates may then be heat treated to reduce areverse curl or induce a positive curl as previously described and/orthe laminates may be maintained or held in the arranged position for aduration of time so that a reverse curl is reduced or a positive curl isinduced (i.e., a positive curl shape memory is induced, the polymericfilm material experiences cold working, etc.). In some embodiments, theplurality of laminates are arranged with the closure flap in the closedposition, and/or secured in the closed position, and shipped so that thereverse curl is reduced or the positive curl is induced during shipping.

FIG. 6 illustrates two different laminate configurations 600. The figureshows the surface of the foil or metallized polymeric film sheet innerlayer of both laminates, 602 and 610. Laminate 602 illustrates a commonlaminate configuration with the foil or metallized polymeric film sheetdirectly adjacent to the scrim layer (shown by the fiber mesh). Thescrim mesh may include a plurality of fibers having a defined spacing A,604, and a defined fiber orientation θ, 606. The foil or metallizedpolymeric sheet layer is generally a thin pliable layer of material. Assuch, the scrim fiber mesh often produces contours 608 in the foil ormetallized polymeric sheet layer as the foil or metallized polymericfilm sheet conforms to the individual fiber strands directly underneaththe foil or metallized polymeric film sheet. The contours may produceareas where the foil or metallized polymeric material is more prone todamage such as scrapping, scuffing, tearing, ripping, etc.

In addition, the contours may produce stress concentration points withinthe foil or metallized polymeric sheet, which may increase thelikelihood of tearing, ripping, etc. Likewise, the contours may limitthe amount of stress that may be applied to the foil or metallizedpolymeric sheet layer due to tearing and/or ripping concerns. Thecontours may cause one or more defects (e.g., tearing, scuffing, etc.)to occur to the foil or metallized polymeric sheet during manufacturingand/or use of the laminate. According to one embodiment of the presentinvention, the scrim fiber mesh may be placed away from the foil ormetallized polymeric sheet so that at least one layer of material (e.g.,the porous media layer) is between the scrim and the foil or metallizedpolymeric sheet as illustrated by laminate 610. The layer between thescrim and the foil or metallized polymeric sheet may act as a bufferbetween the layers so that the contours in the foil or metallizedpolymeric sheet are reduced or eliminated (illustrated by the smoothfoil or metallized polymeric sheet surface in laminate 610).

Because the contours may be removed, the foil or metallized polymericsheet may be less prone to scrapping, scuffing, tearing, ripping, etc.and/or the stress concentration points may be removed. This may allowthe foil or metallized polymeric sheet to be placed under greatertension without ripping or tearing the foil or metallized polymericsheet. The layer directly adjacent the foil or metallized polymericsheet (e.g., the porous media layer) may further add structural supportto the foil or metallized polymeric sheet. The increased tensioning ofthe foil or metallized polymeric sheet and/or the added structuralsupport may allow the reverse curl to be reduce or a positive curl to beinduced through controlled tensioning described in relation to FIG. 3.The removal or the contours and/or the added structural support may alsominimize the defects that occur during manufacturing and or use. Theremoval of defects in the foil or metallized polymeric sheet mayincrease the perm rating of the laminate (i.e., may provide a moreimpermeable layer to water vapor and/or other contaminants).

In addition, the scrim may be placed directly adjacent to the polymericfilm sheet outer layer, which may add structural support and/orstability to the polymeric film sheet outer layer. The added structuralsupport and/or stability may limit the heat shrinkage of the polymericfilm sheet outer layer and/or allow for greater control over thetensioning of the polymeric film sheet layer. The added structuralsupport and/or stability of the polymeric film sheet may reduce theamount of reverse curl that the closure flap experiences.

FIG. 7 illustrates various scrim fibers 700 that may be used to reduce areverse curl or induce a positive curl. Fiber 702 may be a straightfiber having a defined diameter 706. The fiber 702 may be biased towardthe straight position, which may impede closure and sealing of thelaminate's closure flap due to a force produced by the fiber 702 as thefiber 702 is forced to bend away from the straight position. As thediameter 706 of the fiber 702 is increased, the force produced when thefiber is bent from the straight position may also increase. The fibermesh of the scrim may be designed to have a specific configuration andfiber spacing (see spacing A and orientation θ of FIG. 6) based on thediameter 706 of the fibers 702 used in the scrim. Closure and/or sealingof the closure flap may be facilitated by reducing the diameter 706 ofthe fibers 702 used and adjusting the fiber configuration and spacingaccordingly. The decreased diameter 706 of the fibers 702 may reduce theforce produced when the fibers 702 are bent from the straight position(i.e., smaller and more tightly spaced fibers may reduce a forceproduced by the scrim to flatten out the laminate).

Similarly, the use of lighter weight fibers, more flexible fibers,and/or fiber pattern geometry (i.e., the spacing and/or orientation ofthe fibers—see A and 0 of FIG. 6) may further reduce a force producedwhen the fibers 702 are bent from the straight position. Additionally,fibers could be used that produce a positive curling force in thepolymeric film sheet. Fiber 704 illustrates a fiber that may produce apositive curling force. The positive curl may be induced in the fiber704 when the fiber is stretched, heated, exposed to a chemical, etc.Similarly, the fiber 704 may be included in the scrim and laminate sothat after inclusion in the laminate, the fiber scrim mesh provides apositive curling force on the laminate.

As previously described, the polymeric film sheet outer layer may shrinkduring and/or after manufacturing of the laminate. The shrinkage may bedue to the exposure of the polymeric film sheet to heat. The heat may beprovided by the adhesive used to bond the layers of the laminate and/orused to bond the laminate with the insulating material (e.g., hot meltadhesive) and/or may be provided by residual heat present in theinsulating material when the laminate is bonded to the insulatingmaterial (the insulating material may have residual heat due to one ormore manufacturing processes). The heat from the adhesive and/or theresidual heat present in the insulating material may conduct through theinner layers of the laminate to the polymeric film sheet outer layer.Upon exposure to the heat, the polymeric film material may shrink, whichmay cause internal stress or tension that results in reverse curling ofthe closure flap.

To reduce the amount of reverse curl in the closure flap, the polymericfilm sheet's exposure to heat may be minimized by strictly controllingthe temperature of the adhesive so that the adhesive is not applied inexcess of the temperature needed and/or by exposing the insulatingmaterial to one or more cooling processes (i.e., the insulating materialmay be brought to near ambient temperature). Minimizing the polymericfilm sheet's exposure to heat may minimize the polymeric film material'sheat shrinkage, which may reduce the closure flap's reverse curl.

FIG. 8 illustrates a flow diagram 800 of a method for manufacturing apipe insulation product according to one embodiment of the presentinvention. At block 805, a foil or metallized polymeric sheet may beprovided. The foil or metallized polymeric sheet may form an inner layerof the laminate and may provide a fluid vapor barrier to minimize fluidvapor transmission through the laminate. At block 810, a polymeric sheetmaterial may be provided. The polymeric sheet material may form an outerexposed layer of the laminate and may include a closure flap that isconfigured to adhesively seal opposite sides of the laminate jacket sothat the laminate forms a hollow cylindrical tube. The closure flap maycurl toward the closed position (or may be configure to curl more towardthe closed position) to provide a greater closure flap adhesive sealbond.

At block 815, a scrim may be provided. The scrim may include a mesh of aplurality of fibers and may be positioned between the foil or metallizedpolymeric sheet and the polymeric sheet outer layer. At block 820, aporous media sheet material may be provided. At block 825, the foil ormetallized polymeric sheet material, the scrim, the porous media sheetmaterial, and the polymeric sheet material may be bonded together via anadhesive material to form the laminate jacket. At block 830, the closureflap may be configured so that the closure flap includes a curl thatprovides a greater closure flap adhesive seal bond.

At block 835 a tubular core of insulating material may be positionedrelative to the laminate so that the tubular core can be wrapped orencased within the laminated. At block 840, the laminate and tubularcore may be bonded together to form the pipe insulation product. Thepipe insulation product may be flexible so that the tubular core andlaminate can be opened, placed about a pipe, and closed withoutdegrading the laminate jacket. At block 845, the pipe insulation productmay be fitted about a pipe to insulate and/or protect the pipe asdescribed previously.

In describing the invention, certain embodiments have been used toillustrate the invention and the practices thereof. However, theinvention is not limited to these specific embodiments as otherembodiments and modifications within the spirit of the invention willreadily occur to those skilled in the art on reading this specification.Thus, the invention is not intended to be limited to the specificembodiments disclosed, but is to be limited only by the claims appendedhereto.

As used herein and in the appended claims, the singular forms “a”, “an”,and “the” include plural referents unless the context clearly dictatesotherwise. Thus, for example, reference to “a process” includes aplurality of such processes and reference to “the device” includesreference to one or more devices and equivalents thereof known to thoseskilled in the art, and so forth.

Also, the words “comprise,” “comprising,” “include,” “including,” and“includes” when used in this specification and in the following claimsare intended to specify the presence of stated features, integers,components, or steps, but they do not preclude the presence or additionof one or more other features, integers, components, steps, acts, orgroups.

What is claimed is:
 1. A pipe insulation product comprising: a tubularcore of insulating material, the tubular core comprising: a length and alongitudinal axis; a substantially cylindrical outer surface; asubstantially cylindrical inner surface; and a wall extending betweenthe cylindrical outer surface and the cylindrical inner surface, thewall having a radially extending thickness and a slit extendingcompletely there through, the slit extending parallel to thelongitudinal axis of the tubular core for the length of the tubularcore; and a laminate that is roughly rectangular in shape and that iscoextensive with and bonded to the substantially cylindrical outersurface of the tubular core and flexible so that the tubular core andlaminate can be opened, placed about a pipe, and closed withoutdegrading the laminate, wherein the laminate comprises: a polymeric filmsheet forming an outer exposed layer of the laminate; a foil ormetallized polymeric sheet material that provides a fluid vapor barrierto minimize fluid vapor transmission through the laminate; a scrimcomprising a mesh of a plurality of fibers; a porous media sheet; and anadhesive, wherein the adhesive bonds the foil or metallized polymericsheet material, the scrim, the porous media sheet, and the polymericfilm sheet together to form the roughly rectangular laminate; wherein:the laminate comprises a closure flap configured to seal opposite sidesof the laminate in a closed position so that the laminate forms asubstantially cylindrical tube with at least a portion of the tubularcore enclosed therein; and the closure flap is concave to provide agreater closure flap seal.
 2. The pipe insulation product of claim 1,wherein: the foil or metallized polymeric film sheet forms an innerlayer of the laminate; the porous media sheet is positioned immediatelyadjacent to the foil or metallized polymeric film sheet so that the foilor metallized polymeric film sheet lies substantially flat against theporous media sheet; and the configuration of the substantially flat foilor metallized polymeric film sheet provides an improved perm rating forthe laminate.
 3. The pipe insulation product of claim 1, wherein theclosure flap is configured to be concave by controlling an amount oftension in the polymeric sheet material and controlling an amount oftension in one or more of the other layers during lamination of thelayers so that, after lamination, the tension in the polymeric sheetmaterial is less than the tension in the one or more of the otherlayers.
 4. The pipe insulation product of claim 1, wherein the closureflap is configured to be concave by: securing the closure flap in theclosed position; heat treating the laminate to soften the polymericsheet material; and cooling the polymeric sheet material so that thepolymeric sheet material hardens with the concave closure flap.
 5. Thepipe insulation product of claim 1, wherein the closure flap isconfigured to be concave by: arranging at least one laminate so that theclosure flap is positioned in the closed position; and maintaining thelaminate with the closure flap in the closed position for a period oftime, wherein after the period of time shape memory is induced in theclosure flap.
 6. The pipe insulation product of claim 1, wherein theclosure flap is configured to be concave by positioning the scrimbetween the porous media material and the polymeric sheet material toeither: provide improved control over the tensioning of one or more ofthe polymeric sheet material, the porous medial material, and the foilor metallized polymeric sheet material; or provide increased stabilityto the polymeric sheet material.
 7. The pipe insulation product of claim1, wherein the closure flap is configured to be concave by either:controlling the temperature of an adhesive used to bond the laminate andtubular core to minimize heat dissipation from the adhesive to thepolymeric sheet material; or cooling the tubular core of insulatingmaterial to roughly ambient temperature prior to bonding the tubularcore and the laminate to minimize heat dissipation from the insulatingmaterial to the polymeric sheet material.
 8. The pipe insulation productof claim 1, wherein the closure flap is configured to be concave byeither: controlling the size and configuration of the fibers of thescrim fiber mesh to reduce a convex configuration of the closure flap;or configuring the scrim fiber mesh to include one or more fibersconfigured to provide the closure flap with the concave configuration.9. The pipe insulation product of claim 1, wherein the porous mediasheet comprises a kraft paper between the range of 25 and 35 pounds per3000 square feet to further provide a greater closure flap seal byincreasing the flexibility of the laminate.
 10. A method ofmanufacturing a laminate, the method comprising: providing an innerlayer comprising a foil or metallized polymeric sheet material, theinner layer comprising: a length, a width, a first face, and a secondface, wherein the length and width form an area that define the firstface and the second face; positioning an outer layer such that thesecond layer is coextensive with the second face, wherein the outerlayer comprises a polymeric sheet material; positioning an intermediatelayer between the inner layer and the outer layer, wherein theintermediate layer provides reinforcement for the laminate; applyingtension to each of the inner layer, the intermediate layer, and theouter layer; and compressing the inner layer, the intermediate layer,and the outer layer together using a plurality of rollers to form asingle multilayered laminate.
 11. The method of manufacturing a laminateof claim 10, wherein: the outer layer comprises a closure flap.
 12. Themethod of manufacturing a laminate of claim 11, wherein: tension appliedon the outer layer is greater than tension applied to the inner layerand the intermediate layer, thereby causing the closure flap to curlaway from a closed position.
 13. The method of manufacturing a laminateof claim 11, wherein: tension applied on the outer layer is less thantension applied to the inner layer and the intermediate layer, therebycausing the closure flap to curl toward a closed position.